论文标题
爱在哪里？黑洞紧凑型极限的潮汐变形性
Where is Love? Tidal deformability in the black hole compactness limit
论文作者
论文摘要
重力的宏观可测量效应之一是天体物理对象的潮汐变形性，可以通过其潮汐爱数量来量化。对于行星和恒星，这些数字测量了其材料对潮汐力的抗性，以及对重力多极矩的贡献。根据一般相对论，非旋转变形的黑洞不显示其重力多极矩的增加，并且它们的所有爱数都是零。在本文中，我们探讨了非旋转紧凑和超级反应星的不同配置，以弥合黑洞和中子星之间的紧凑差距，并计算其爱情编号$ k_2 $。 We calculate $k_2$ for the first time for uniform density ultracompact stars with mass $M$ and radius $R$ beyond the Buchdahl limit (compactness $M/R > 4/9$), and we find that $k_2 \to 0^+$ as $M/R \to 1/2$, i.e., the Schwarzschild black hole limit.我们的结果提供了对零潮汐可变形性限制的见解，我们对GW170817的二进制潮汐变形性$ \tildeλ$（以及二进制黑洞合并的未来上限）使用当前约束来提出替代模型的测试。
One of the macroscopically measurable effects of gravity is the tidal deformability of astrophysical objects, which can be quantified by their tidal Love numbers. For planets and stars, these numbers measure the resistance of their material against the tidal forces, and the resulting contribution to their gravitational multipole moments. According to general relativity, nonrotating deformed black holes, instead, show no addition to their gravitational multipole moments, and all of their Love numbers are zero. In this paper we explore different configurations of nonrotating compact and ultracompact stars to bridge the compactness gap between black holes and neutron stars and calculate their Love number $k_2$. We calculate $k_2$ for the first time for uniform density ultracompact stars with mass $M$ and radius $R$ beyond the Buchdahl limit (compactness $M/R > 4/9$), and we find that $k_2 \to 0^+$ as $M/R \to 1/2$, i.e., the Schwarzschild black hole limit. Our results provide insight on the zero tidal deformability limit and we use current constraints on the binary tidal deformability $\tildeΛ$ from GW170817 (and future upper limits from binary black hole mergers) to propose tests of alternative models.
